Automatic switch



Jan. 11, 1949. c, CLEMENT I 2,459,015 I AUTOMATIC SWITCH Filed Aug. 14, 1945' 2 Sheets-Sheet l glvwwwm CEUZemenf Patented Jan. 11, 1949 UNITED AUTOMATIC "SWITCH Application August 14, 1945, Serial No. 610,771

lzGlaim. l

This invention relates to a safety switch and circuit construction for motion picture-houses.

An object of this invention isto provide-an improved switch 1 construction which-is connected to the electric circuits of projeotion machines, the tire alarmsystem and otherelectric circuits so that in the event of fire the firealarm, which may Joe-remote from theprojection room, will be energized and the mainhouse lights, which are normallycut off during-the showing of a picture, will be turned on in order that; people in the theater will be able'to leave the theater more rapidly than is the case where they leave 'the theater with the lights off.

A further object of" this invention'is to provide an improved switch structure of this kind which is simple in construction, and --automatically moves from. a normal positionrclosing the electric circuits to the projection apparatus:to'. a disengaging position cuttingofftheprojection apparatus and closing the fire alarm circuit and other circuits associated-therewithwhich are normally oif during'the operationof the projection apparatus.

A further object of this invention is toprovide a switch of this kind-which is normally-held in uppermostposition closing the normal circuits by a frangible connection which is connected-to the shutter bar which .automatically closes the shutter in the forward wall of the projection booth.

With the foregoing objects in view, and others which may hereinafter more "fully appear the invention consists of the novel'construetlon, combination andarrangcmentof partsas will be more specifically described, and illustrated in the accompanying drawings wherein are shownembojdiments of the invention, but'it is tobe' understood that changes, variations and modifications may be resorted to which fall within the scope of the invention, as claimed.

In the drawings:

Figure 1 is a detail front elevation of a switch constructed according to an embodiment of this invention.

Figure 2 is a detail side elevation, partly broken away and in section, of the switch.

Figure 3 is a sectional view taken on the line 3-3 of Figure 2.

Figure 4 is a sectional view taken on the line 4-4 of Figure 2.

Figure 5 is a sectional view taken on the line 5-5 of Figure 1.

A switch assembly, generally designated as 25, is interposed in the circuits of the motors, lamps and switch for-'thefire extinguisher in a projection room, and includes'anupper stationary insulatedbody-QG which is adapted'to be secured by fastening members 21 to a panel 28.

A lowerstationarybod-y 29, of insulated constructiomis also secured-to thepanel 28 by fastening members 30in a position-spaced downwardly-from the upper body 26. The upper body 26' has-'secured thereto pairs of contact members 31-, 32,33 and 34. The contact-members 3| to 34am secured to'bolts or terminals 35, 36, 31 and 38 which are pos-itioned above-the body 25. The lower'stationary body whas mounted on the upper side thereof spaoed'pairs of contact members 33,-40,'-4I and 42,- which are carried by terminal members43','44, 45 and 46 respectively.

An intermediate movable insulated body 41 is disposed between'thetwo bodies 25 and 29 and has secure'dto the upper side-thereof a plurality of contact bridging members of substantially U-shape-and-designated by the-numerals 48, 49, 50 and 5|.

The several -bridgingmembers 48 to 5| are secured in recesses' 5l which are formed in the body 41 beingsecured in the recesses 52 by screws 53 which are threaded into embedded nuts 56 carried by the body 41. The bridging member "is adapted-tobri'dge the pairs of contacts 3! andthe bridging member bridges contacts 32. Thebridgingmember 50 bridges contacts 53, and the bridging member 51 bridgescontacts 54.

"A plurality of inverted U-shaped bridging members 55, 56, 51 and 58, which are similar in construction to the bridging members 48 to 5 I, are disposed in a recess 59 formed in the lower side of the body 41, and secured therein by fastening screws fiflwhich arethreaded into embedded nuts 51.

Bridging member'55 bridges the two contacts 39;bridgingmember'fli'bridges the two contacts 40; bridging member 51 bridges'the two contacts 4|; and'bridging member 58 bridges the two contacts. 42.

The movable contact carrier 41 is fixedly secured *to a pair of vertically disposed bars 62 and 63 whlchare slldable through openings in the stationary bodies 25 and 29, and are fixed to the contact carrier 41 by set screws 64 and 65 respectively.

The carrier 41 is constantly urged downwardly to a position where the bridging members to 58 will bridge the contacts 39 to 42 by means of springs 66 and 61 which, at their upper ends,

bear against the lower side of the lower body 29, and at the lower ends bear against tensioning nuts 68 and 69 threaded on the lower ends of the slide bars 62 and 63 respectively.

A connecting bar connects the upper ends of the slide bars 62 and 63 together being secured on the ends of these bars by nuts H and 72. The center of the bar 10 has an eye I3 secured thereto and one end of a spring 14 is engaged with the eye '13. A link 15 is connected at its upper end to a lever arm 16 carried by the shutter operating bar 24 and a fusible member 11 is connected between the spring 14 and the lower end of the link 15.

The spring 14, with the linkage connecting this spring with the lever arm '16, are adapted to maintain the movable circuit-breaking and closing carrier 41 in its uppermost and normal operating position. v

The upper terminals to 38, which are in pairs, have one member of each pair connected to a common supply wire 18 by means of wires 19, 89, BI and 82. The other member of pair 35 is connected by means of a wire 83 to one side of the motor 10, and the other member of pair 36 is connected by awlre 84 to one side of the lamp l2. The other sides of the motor and lamp are connected to the ground through a common ground wire 85. The other member of pair 37 of terminals is connected by means of a wire 86 to one side of the lamp [3, and the other member of the pair 38 is connected by means of a wire 81 to one-side of the motor ll. The other sides of the motor II and the lamp 13 are connected to a return or ground by a common conductor 88.

One member of each of the lower pairs of contacts 39 to 42 are connectedto the positive side of the supply source by means of conductors 89, 90, 9| and 92. The wires 89 to 92 are connected through a common wire 93 to the supply wire 78. A wire 94 connects the other member of the pair of contacts 39 to the main houselight circuit, being adapted to form a shunt in this circuit for closing the circuit irrespective of the position of the main house switch.

The other member of the pair of contacts is connected by means of a conductor 95 to one side of the solenoid or electric operator 96 for the valve 23. The opposite side of the operator 96 is connected to the return line by a ground 91. The other member of the pair of contacts 4! is connected to a slide lamp by means of a conductor 98. The slide lamp may be a projection apparatus for projecting still pictures on the screen, orfor projecting instructions or other material onto the screen during an emergency, such as a fire, or the like.

The other member of the pair of contacts 42 is connected to a fire alarm system by means of a wire 99 so as to close the circuit to the fire alarm when the carrier 41 is lowered to its lowermost emergency position. I

In the use and operation of this switch structure the several terminals are connected to the circuits, as hereinbefore described, and in the normal operating position the carrier 41 is in its uppermost position whereby the projection apparatus may be operated in the normal manner and the projection apparatus may be disengaged from the supply source by means of a main switch I00 which is interposed in the positive wire "1'8.

In the event a fire should occur in the projection room so as'to either cause the shutter bar 24 to rotate in a clockwise direction, as viewed in Figure 2, or the heat in the projection room should cause fuse Tl tomelt, spring 36 and 61 'will move carrier 41 downwardly so as to cut off the electric circuits to the projection motors and the lamps and at the same time to close the circuits to the valve operator connected with the carbon dioxide tank and to the fire alarm, the main houselighting circuit and the slide lamp circuit.-

It will be understood that additional circuits may be closed 'or' broken, as may be desired, it only being necessary to add additional pairs of contacts with bridging members to the carrier 4'1 and the stationary bodies 25 and 29.

I claim:

An automatic switch for use in connection with the shutter holding rod of a motion picture projection room comprisin a pair of fixed insulated stationary bodies disposed in spaced relation one to the other, pairs of contacts carried by the confronting sides of said bodies, a movable circuit closing member disposed between said bodies, bridging contacts carried by one side of said member for engagement with the contacts of one of said bodies, oppositely disposed bridging contacts carried by the opposite side of said member for engagement with thecontacts of said other body, a pair of slide bars fixed to said member and loosely engaging through said bodies, a connecting bar connecting the end of one bar to the other bar, springs about said pair of bars outwardly of one of said bodies for constantly urging said member to move in the direction of the other of said bodies, elongated yieldable means connected between said connecting bar and said shutter holding rod for normally maintaining said member in a position with the bridging contacts on the first-named side thereof in engagement with the pairs of contacts of said other body and a fusible element interposed in said latter named means.

CLYDE H. CLENENT.

REFERENCES CITED Thef ollowing references are of record in the file of this patent:

I UNITED STATES PATENTS Number Denmark Feb. 10, 1925 

